Extended Depth Of Field Research Articles

Patient Satisfaction and Visual Function Following Implantation of Trifocal or Extended Range of Vision Intraocular Lenses.

PurposeTo compare the trifocal TFNT00 and extended depth-of-focus (EDF) ZXR00 intraocular lenses (IOLs) with respect to overall satisfaction with near and distance vision, visual acuity, dysphotopsia symptoms, spectacle dependence, and mesopic best corrected contrast sensitivity (MBCCS).Materials and MethodsThis non-randomized, retrospective, single-centre, comparative study took place at the Kensington Eye Institute in Toronto, Canada. Subjects implanted with either the TFNT00 IOL (n = 11) or ZXR00 IOL (n = 13) were assessed up to 4 years post operatively. Overall satisfaction with distance and near vision, corrected distance visual acuity, uncorrected visual acuity at distance, intermediate (60 cm) and near (40 cm) (UNVA), dysphotopsia symptoms, spectacle dependence and monocular MBCCS were evaluated.ResultsForty-eight eyes of 24 subjects (mean age 68 years, 54% female) were assessed. There was no difference in overall satisfaction; both groups had a median score of 10/10 for overall distance vision, and 7/10 and 8/10 for near vision for EDF and trifocal, respectively. MBCCS at the higher spatial frequencies was significantly better with the ZXR00 IOL. Potentially clinically relevant but not statistically significant differences were found; the trifocal group (vs the EDF group) had better binocular UNVA (20/24 vs 20/32) and less spectacle dependence at least some of the time (54% vs 85%).ConclusionThe ZXR00 may be preferred for those who want optimal contrast sensitivity in dim lighting. Consistent with previous studies, the TFNT00 trifocal IOL may be a better choice for those who want to optimize UNVA. More studies in North America are required to further investigate spectacle dependence.

Influence of angle alpha on visual quality after implantation of extended depth of focus intraocular lenses

BackgroundTo assess postoperative changes in angle alpha, and to evaluate the postoperative visual quality of patients with different angle alpha values after implantation of extended depth of focus (EDOF) intraocular lenses (IOLs).MethodsSeventy-nine eyes of 79 patients who had phacoemulsification with EDOF IOLs implantation were enrolled. A cut-off value of 0.3 mm, 0.4 mm, and 0.5 mm in preoperative angle alpha was chosen to divide eyes into groups. Distance, intermediate, and near visual acuities, modulation transfer function (MTF), and aberrations were recorded during a 6-month follow-up. A patient questionnaire was completed.ResultsThere were no significant differences in angle alpha postoperatively compared to preoperatively. No significant differences were found in visual acuity and MTF between all groups. With 5 mm pupil diameter, there were significant differences of higher-order aberrations and spherical aberration in ocular aberration and internal aberration between angle alpha<0.4 mm and angle alpha≥0.4 mm. Additionally, significant differences of coma were also added in cut-off value of 0.5 mm. When the value of angle alpha is 0.4 mm or higher, there were significant differences in the score of halos and glare.ConclusionsAngle alpha did not affect visual acuity, but the value of 0.4 mm or higher in angle alpha affected the visual quality under scotopic conditions and occurrence of halos and glare. For patients with 0.4 mm or higher in angle alpha, the choice to implant a EDOF IOL should be carefully considered.

A high-resolution photogrammetric workflow based on focus stacking for the 3D modeling of small Aegean inscriptions

Any attempt of decipherment and language identification of the scripts from the Aegean dating to the second millennium BCE (namely Cretan Hieroglyphic, Linear A, and Cypro-Minoan) has relied, until today, on traditional catalogues of inscriptions, consisting of incomplete or subjective 2D representations, such as photographs and hand-drawn copies, which are not suitable for documenting such three-dimensional writing systems. In contrast, 3D models of the inscribed media allow for an accurate and objective “autopsy” of the entire surface of the inscriptions. In this context, this work presents an efficient, accurate, high-resolution, and high-quality texture photogrammetric workflow based on focus-stacked macro images, designed for the 3D modeling of small Aegean inscriptions, to properly reconstruct their geometry and to enhance the identification of their signs, making their transcription as unbiased as possible. The pipeline we propose also benefits from a pre-processing stage to remove any coloration difference from the images, and a reliable and simple 3D scaling procedure. We tested this workflow on six inscribed artifacts (two in Cretan Hieroglyphic, three in Linear A, one of uncertain affiliation), whose average size ranges approximately from 1 to 3 cm. Our results show that this workflow achieved an accuracy of a few hundredths of mm, comparable to the technical specifications of standard commercial 3D scanners. Moreover, the high 3D density we obtained (corresponding to the edge average length of the 3D model mesh), up to ≈ 30 µm, allowed us to reconstruct even the smallest details of the inscriptions, both in the mesh and in the texture layer of the 3D models.

Nondiffractive wavefront-shaping extended depth-of-focus intraocular lens: visual performance and patient-reported outcomes.

To evaluate visual performance and patient-reported outcomes after bilateral implantation of a new nondiffractive wavefront-shaping extended depth-of-focus (EDoF) intraocular lens (IOL). Department of Ophthalmology, Goethe University, Frankfurt, Germany. Prospective, single-arm, single-center study. Patient population: 16 patients (32 eyes) who received bilateral implantation of a nondiffractive wavefront-shaping EDoF IOL (AcrySof IQ Vivity) were included. Target refraction in both eyes was emmetropia. Observation procedure: Monocular and binocular uncorrected (UCVA) and distance-corrected (DCVA) visual acuity (VA), refractive outcome, defocus curve, and contrast sensitivity (CS) were evaluated 3 months after surgery with a questionnaire on optical phenomena and spectacle independence. Main outcome measure: 3-month postoperative monocular and binocular UCVA and CDVA (logMAR), defocus curve, CS, and quality of vision (QoV) questionnaire results. 16 patients with 32 eyes were included. Mean spherical equivalent was -0.16 ± 0.37 diopters (D) 3 months postoperatively. Binocular uncorrected distance VA at distance, intermediate, and near was 0.01 ± 0.05 logMAR at 4 m, 0.05 ± 0.05 logMAR at 80 cm, 0.07 ± 0.06 logMAR at 66 cm, and 0.25 ± 0.11 logMAR at 40 cm, respectively. Despite some minor optical phenomena, 88% of patients would choose the same lens. 63% of patients reported no optical phenomena at all. CS was 1.25 ± 0.41 logCS (photopic), 0.96 ± 0.24 logCS (mesopic), and 0.93 ± 0.24 (mesopic + glare). This nondiffractive wavefront-shaping EDoF IOL provides good VA at far and intermediate distance and functional near VA. It showed good QoV and CS and high spectacle independence for distance and intermediate vision with significantly less optical phenomena than with other EDoF or multifocal IOLs.

Influence of the fitting rule of Extended Depth of Focus contact lenses on visual performance of high addition presbyopic patients

Purpose: Recommended fitting rule for Extended Depth of Focus (EDOF) contact lenses is to use medium addition in the non-dominant eye and high addition in the dominant eye when spectacle addition is higher or equal to 2.00D. The purpose of this study was to evaluate the influence of different additions in the optical performance of high addition presbyopic patients with EDOF contact lenses through defocus curves.

Visual outcomes of a new nondiffractive extended depth-of-focus intraocular lens targeted for minimonovision: 3-month results of a prospective cohort study.

To evaluate visual outcomes, spectacle independence, and optical phenomena after bilateral implantation of a nondiffractive extended depth-of-focus (EDoF) intraocular lens (IOL) targeted for minimonovision. University Eye Clinic Maastricht, the Netherlands. Prospective case series. Patients with age-related cataract were bilaterally implanted with a nondiffractive EDoF IOL (Alcon AcrySof IQ Vivity), targeted for minimonovision. Outcome measures were the uncorrected distance visual acuity (UDVA), corrected distance visual acuity, uncorrected intermediate visual acuity (UIVA), uncorrected near visual acuity (UNVA), distance corrected intermediate visual acuity, distance corrected near visual acuity, refractive outcomes, defocus curves, spectacle independence, photic phenomena, and Catquest-9SF questionnaire. 44 eyes of 22 patients were included. The mean binocular UDVA, UIVA, and UNVA were -0.07 (±0.10), 0.04 (±0.09), and 0.23 (±0.12) logMAR, respectively. The percentage of eyes within ±1.0 diopters (D) and ±0.5 D of target was 100% and 95% for the dominant eye and 100% and 86% for the nondominant eye, respectively. The binocular defocus curve was better than 0.10 logMAR over a range from -2.0 D to +0.5 D. The percentage of patients who reported not or rarely using spectacles for distance, intermediate, and near viewing distance was 96%, 68%, and 38%, respectively. The percentage of patients who experienced no halos, glare, or starbursts were 91%, 91%, and 100%, respectively. The Catquest-9SF showed a high patient satisfaction for daily life activities. Bilateral AcrySof IQ Vivity IOL implantation targeted for minimonovision provided good visual acuity results for far and intermediate with functional near vision, high level of patient satisfaction and spectacle independence, and a monofocal disturbance profile.

Content aware multi-focus image fusion for high-magnification blood film microscopy.

Automated digital high-magnification optical microscopy is key to accelerating biology research and improving pathology clinical pathways. High magnification objectives with large numerical apertures are usually preferred to resolve the fine structural details of biological samples, but they have a very limited depth-of-field. Depending on the thickness of the sample, analysis of specimens typically requires the acquisition of multiple images at different focal planes for each field-of-view, followed by the fusion of these planes into an extended depth-of-field image. This translates into low scanning speeds, increased storage space, and processing time not suitable for high-throughput clinical use. We introduce a novel content-aware multi-focus image fusion approach based on deep learning which extends the depth-of-field of high magnification objectives effectively. We demonstrate the method with three examples, showing that highly accurate, detailed, extended depth of field images can be obtained at a lower axial sampling rate, using 2-fold fewer focal planes than normally required.

Visual performance of a new Extended Depth of Focus (EDOF) intraocular lens: Preliminary results

To evaluate visual outcomes at 3 months after bilateral implantation of a new EDOF intraocular lens in a routine cataract population. Prospective evaluation of 12 patients (24 eyes) implanted bilaterally with an EDOF intraocular lens (IOL) with emmetropia as the target. Visual acuity at distance, intermediate (70cm) and near (40cm) with and without distance correction, refractive error, monocular photopic defocus curve and contrast sensitivity curve with best corrected distance refraction were measured. Subjective outcomes in terms of visual function, spectacle independence, lighting independence, dysphotopsia and overall satisfaction were assessed at three months. The mean age of the patients was 68.33 years±10.30. The mean IOL power was 21.5±2.44D. Three months after surgery, the mean decimal uncorrected distance (UCDVA), intermediate (UCIVA) and near (UCNVA) visual acuities were 0.10, 0.09 and 0.23 logMAR respectively. The monocular defocus curve with distance correction showed 1.75D of depth of field with an acuity better than 0.3 logMAR. Patient satisfaction was high, with a low occurrence of dysphotopsia. The A-constant should be optimized for better predictability. The EDOF IOL showed satisfactory visual performance after cataract surgery, with high patient satisfaction and a low occurrence of visual disturbances. It resulted in good distance and intermediate vision, but might require spectacles for small print at a near distance.

Image Quality Evaluation of Light Field Image Based on Macro-Pixels and Focus Stack.

Due to the complex angular-spatial structure, light field (LF) image processing faces more opportunities and challenges than ordinary image processing. The angular-spatial structure loss of LF images can be reflected from their various representations. The angular and spatial information penetrate each other, so it is necessary to extract appropriate features to analyze the angular-spatial structure loss of distorted LF images. In this paper, a LF image quality evaluation model, namely MPFS, is proposed based on the prediction of global angular-spatial distortion of macro-pixels and the evaluation of local angular-spatial quality of the focus stack. Specifically, the angular distortion of the LF image is first evaluated through the luminance and chrominance of macro-pixels. Then, we use the saliency of spatial texture structure to pool an array of predicted values of angular distortion to obtain the predicted value of global distortion. Secondly, the local angular-spatial quality of the LF image is analyzed through the principal components of the focus stack. The focalizing structure damage caused by the angular-spatial distortion is calculated using the features of corner and texture structures. Finally, the global and local angular-spatial quality evaluation models are combined to realize the evaluation of the overall quality of the LF image. Extensive comparative experiments show that the proposed method has high efficiency and precision.

Capture optimization for composite images

A composite image is an image created by combining portions of multiple separately-captured images. Stitching of captures of tiled portions of a larger scene can be used to produce a single composite image (a panorama) with a wider view angle and higher total resolution. Image stacking is a different type of compositing, in which the scene is not changing significantly across captures, but camera parameters might be systematically varied. Focus stacking can extend the depth of field, aperture stacking can implement apodization shaping the out-of-focus point spread function, and noise and motion reduction can be accomplished even using the same camera parameters for each capture to be stacked. These and other compositing methods are well known and commonly used, but the same fixed pattern is commonly used for ordering of captures and choice of capture parameters. This paper examines the problem of static, pseudo-static, or dynamic determination of the optimal capture parameters and ordering.

Polychromatic through-focus image quality in a wavefront-shaping presbyopia correcting intraocular lens

ABSTRACT Objectives To compute the polychromatic through-focus image quality in eyes implanted with a new extended depth of focus (EDOF) intraocular lens (IOL). Methods Eight eyes of four patients who underwent implantation with the AcrySof IQ Vivity EDOF IOL were analyzed. Wavefront aberrations were measured. The optical metric for the polychromatic through-focus image quality used was the Visual Strehl ratio computed in the spatial domain (VSX). Eight eyes implanted with a monofocal IOL were also examined. Results The normalized VSX values change with vergence for both group of IOLs. However, the depth-of-focus (DoF) for the Vivity IOL was about 0.75, 1.00, and 1.25 D larger than the monofocal IOL, for 0.1, 0.2, and 0.3 logMAR visual acuities. The DoF computed from the polychromatic through-focus image quality for the Vivity IOL was about 2.50D, being this value 1.25D wider than the monofocal one. The DoF obtained from the defocus curve was about 2.25 D for eyes implanted with the Vivity IOL. Conclusions Polychromatic through-focus image quality analysis agrees with the clinical outcomes indicating that this methodology may be useful to estimate the DoF and the expected quality of vision in patients implanted with lenses from wavefront aberration measurement. This approach shows the increased DoF of the EDOF lens compared to a monofocal.

Outcomes of bilateral implantation of trifocal and extended depth of focus IOLs

Comparative analysis of the results of trifocal and EDOF IOL implantation in patients with presbyopia and/or cataract. This prospective study included 72 patients (144 eyes) after bilateral implantation of either Tecnis Symfony EDOF IOL (18 patients, 36 eyes; group I) or AcrySof PanOptix trifocal IOL (54 patients, 108 eyes; group II). In 18 patients out of 72 (25%) the implantation involved mini-monovision, i.e. the calculation of the IOL power on the nondominant eye was performed at -0.5 D. The average follow-up period for the patients was 7.1±1.2 months. There was a significant (p<0.05) increase in uncorrected near visual acuity (UCNVA), uncorrected intermediate visual acuity (UCIVA) and uncorrected distance visual acuity (UCDVA) at the maximum follow-up time compared to the preoperative indices in all groups. Group II was characterized by slightly better UCNVA dynamics (0.85±0.13 versus 0.2±0.04 before surgery, as comparted to 0.78±0.11 versus 0.19±0.06 before surgery in group I), but differences were not statistically significant (p>0.05). Statistically significant differences (p=0.046) were observed when comparing best corrected near vision acuity (BCNVA) in groups I and II (0.79±0.05 and 0.98±0.08, respectively) at 6 months compared to the preoperative period (0.62±0.09 and 0.6±0.11, respectively). Trifocal IOL implantation was associated with acceptable near and far vision correction and a higher frequency of adverse optical phenomena, while implantation of the EDOF IOL was associated with slightly better correction of intermediate vision and a significantly lower incidence of halo and glare. Patients were satisfied with the outcomes of surgery in all cases.

The Importance of IOL Selection in Patients With Young-age Cataracts: a Case Report

Background: A cataract is a type of degenerative change of the lens, which is characterized by the clouding of the lens followed by symptoms of optical deterioration. Over 70 years ago, Sir Harold Ridley implanted the first useable modern-day intraocular lens (IOL) implant. A lot has happened since then. The IOL is arguably the most life-changing and innovative implant in the history of medicine. Currently, there are several types of intraocular lenses on the market. The main classification could be monofocal lenses, multifocal, trifocal, extended depth of focus (EDOF) lenses, and toric lenses. Objective: The aim of this case report is to report the importance of IOL selection in patients with young-age cataracts. Case report: A 35-year-old patient presented first time at our Clinic. In the last six months, he noticed poor vision in his left eye, even with spectacles. The right eye was operated on in another institution in 2020, due to the presence of a young-age cataract. After a complete preoperative ophthalmological examination, we discovered the presence of a cataract in the left eye. UDVA of the left eye was 0.4, and CDVA was +0.50/+0.50/30°=0.5. UNVA and DCNVA was J2. We decided to implant TECNIS Synergy™ IOL (Johnson &amp; Johnson Vision, Santa Ana, CA, USA) during the cataract surgery. That EDOF IOL bridges the gap between the performance of monofocal and multifocal IOLs and delivers continuous high-contrast vision for patients with cataracts from far through near, even in low-light conditions. There were no intraoperative or postoperative complications. On a 7-day, check-up UDVA of the left eye was 1.0, and UNVA was J1. The patient was satisfied with the vision in the left eye, so he wanted to correct the vision of the right eye which was implanted with SENSAR® IOL (Johnson &amp; Johnson Vision, Santa Ana, CA, USA), with a residual diopter of +2.00/+1.00/120 for distance, and +4.50/+1.00/120 for near vision. This choice of IOL in the other institution was not an ideal solution for this patient due to his young age and occupation. The capsular bag was already in slight fibrosis, so the explantation of the existing IOL and implantation of the new one was not a reasonable option. We decided to go with the multifocal AddOn® toric lens (1stQ GmbH, Mannheim, Germany), the refractive-surgery platform for vision enhancement of pseudophakic eyes, that also correct residual astigmatism. On a 7-day check-up, this patient’s UDVA was 1.0 and UNVA was J1. The result was a happy patient, who could go back to his everyday life without spectacle independence. Conclusion: Good unaided distance visual acuity (VA) is now a realistic expectation following cataract surgery and intraocular lens (IOL) implantation. We should be aware of patient expectations and demands, especially when having a patient with young-age cataracts. Often more time should be spent on preoperative IOL planning than cataract surgery itself.

Clinical outcomes of a monofocal intraocular lens with enhanced intermediate function compared with an extended depth-of-focus intraocular lens.

To compare clinical outcomes of a new monofocal intraocular lens (IOL) with enhanced intermediate function and an extended depth-of-focus (EDoF) IOL. Asan Medical Center, Seoul, Korea. Nonrandomized prospective comparative case series. Patients presenting for cataract surgery and meeting all inclusion and exclusion criteria were implanted with a new monofocal IOL with enhanced intermediate function (Tecnis Eyhance ICB00) or an EDoF IOL (Tecnis Symfony ZXR00) bilaterally. Uncorrected (UDVA), uncorrected intermediate (UIVA), uncorrected near (UNVA), and corrected distance visual acuity (CDVA), defocus curves, and contrast sensitivity were compared after 3 months. Patients were administered questionnaires regarding visual symptoms, spectacle independence, overall satisfaction, and lens recommendations. 24 patients (48 eyes) were enrolled in the Eyhance group and 20 patients (40 eyes) in the Symfony group. Monocular and binocular UDVA, UIVA, and CDVA were similar in the 2 groups. Monocular UNVA and spectacle independence for near distance were better in the Symfony group, whereas binocular UNVA did not differ significantly in the 2 groups. Contrast sensitivity, glare and halo, satisfaction, and recommendation rates were similar in the 2 groups. Although some dissatisfaction and severe glare and halo were reported in the Symfony group, none of these was reported in the Eyhance group. Bilateral implantation of the Eyhance ICB00 IOL provided comparable clinical performances as bilateral implantation of the Symfony ZXR00 IOL. Binocular UNVA was similar, although spectacle independence was higher in the Symfony group, but this was at the expense of more glare and halos.

Objective Quality Assessment of Lenslet Light Field Image Based on Focus Stack

The large amount of complex scene information recorded by light field imaging has the potential for immersive media applications. Compression and reconstruction algorithms are crucial for the transmission, storage, and display of such massive data. Most of the existing quality evaluation indexes do not effectively account for light field characteristics. To accurately evaluate the distortions caused by compression and reconstruction algorithms, it is necessary to construct an image evaluation index that reflects the angular-spatial characteristics of the light field. This work proposes a full-reference light field image quality evaluation index that attempts to extract less information from the focus stack to accurately evaluate the entire light field quality. The proposed framework includes three specific steps. First, we construct a key refocused image extraction framework by the maximal spatial information contrast and the minimal angular information variation. Specifically, the gradient and phase congruency operators are used in the extraction framework. Second, a novel light field quality evaluation index is built based on the angular-spatial characteristics of the key refocused images. In detail, the features used in the key refocused image extraction framework and the chrominance feature are combined to construct the union feature. Third, the similarity of the union feature is pooled by the relevant visual saliency map to obtain the predicted score. Finally, the overall quality of the light field is measured by applying the proposed index to the key refocused images. The high efficiency and precision of the proposed method are shown by extensive comparison experiments.

Comparison of Patient Outcomes following Implantation of Trifocal and Extended Depth of Focus Intraocular Lenses: A Systematic Review and Meta-Analysis.

Purpose The purpose is to compare the outcomes of implantation of trifocal intraocular lenses (TIOLs) and extended depth of focus (EDOF) intraocular lenses (IOLs). Methods A comprehensive search of PubMed, Cochrane Library, EMBASE, and ClinicalTrial.gov was conducted in March 2020 to identify relevant studies. A meta-analysis of the results was performed. Patients implanted with EDOF IOLs or TIOLs in previous studies were included. The primary outcomes of the study were uncorrected distance visual acuity (UDVA), uncorrected intermediate visual acuity (UIVA), uncorrected near visual acuity (UNVA), and defocus curve. Results TIOLs and EDOF IOLs provided comparable binocular UDVA (MD = -0.01, 95% CI: -0.04, 0.03, logMAR). However, EDOF IOLs provided better UIVA (MD: -0.08, 95% CI: -0.14, -0.01, logMAR) and worse UNVA (MD: 0.10, 95% CI: 0.06, 0.14, logMAR) than TIOLs. Fewer patients achieved spectacle independence after implantation of EDOF IOLs (RR: 0.74, 95% CI: 0.63, 0.87) than after implantation of TIOLs, especially for near vision (RR = 0.82, 95% CI: 0.68, 0.99). There was no statistically significant difference in contrast sensitivity (CS) under photopic or mesopic conditions with both IOLs. Patient satisfaction after implantation of both IOLs was high. Conclusion EDOF IOLs and TIOLs provide comparable distance vision. However, EDOF IOLs provide better intermediate vision and worse near vision than TIOLs. The advantages of EDOF IOLs over TIOLs in terms of CS, aberrations, and visual disturbance are not significant. Patients are satisfied with both types of IOLs.

Functional visual acuity after implantation of diffractive extended depth-of-focus intraocular lenses using an echelett optics

BackgroundThe prospective comparative case series aimed to evaluate all-distance visual acuity, contrast sensitivity, and functional visual acuity (FVA) of eyes with diffractive extended depth-of-focus (EDOF) intraocular lenses (IOLs) using an echelett optics and monofocal IOLs with the same platform.MethodsDiffractive EDOF and monofocal IOLs were implanted in 27 eyes of 27 patients each. At 3 months after implantation, all-distance visual acuities at distances of 0.3, 0.5, 0.7, 1, 2, 3, and 5 m were measured under distance-corrected. Static visual function was also examined using photopic contrast sensitivity and area under the logarithmic contrast sensitivity function (AULCSF). Dynamic visual function was examined with FVA, and mean FVA value, visual maintenance ratio (VMR), mean response time, and number of blinks were evaluated. These outcomes were compared between the two IOLs.ResultsThe mean distance-corrected visual acuities were better at distances of 0.7 m or nearer in eyes with EDOF IOLs. There was no difference in the contrast sensitivities (P > 0.22). In the FVA results, no difference was found in mean FVA and VMR (P > 0.68).ConclusionThe static and dynamic evaluations of postoperative visual functions demonstrated that the visual function of eyes with EDOF IOLs under photopic and distance-corrected conditions was comparable to eyes with monofocal IOLs.

Efficient arbitrary polarized light focusing by silicon cross-shaped metaatoms

The functionality of most of the metasurfaces that have been investigated so far, especially in illuminations with arbitrarily linearly polarized incident light, are restricted to x- or y-polarized incoming light. In particular, filtering out one of the two orthogonal polarizations of the incoming electromagnetic wave loses the incident light energy and limits the potential performance of the metasurface. In this study, by utilizing the cross-shaped silicon metaatoms that support the simultaneous excitation of electric and magnetic dipoles under the illumination of both x- and y- orthogonal polarizations, we overcome the polarization-restricted functionality of the metalenses. By selecting the metaatoms arrangement in the metalens structure, which follows the hyperbolic phase profiles for both x- and y-polarized incoming light waves at the same time, we obtain the light intensity distribution with the extended depth of focus (EDOF) or enhanced intensities at the focal spot with the focusing efficiency 65% for the numerical aperture of 0.7. Utilizing metaatoms with the ability to control the two orthogonal incoming polarizations develops a new methodology for using the full potential and intensity of the arbitrary polarized incoming light. The present design concept of metaatoms has several advantages that are not limited to metalenses alone but can be applied in all metasurfaces realized to have good efficiency. Finally, the proposed metalenses are suitable for imaging, optical tweezers and lithography applications, where subwavelength light intensity distributions with EDOF are the most desirable property.

Freeform optics for variable extended depth of field imaging.

Imaging depth of field is shallow in applications with high magnification and high numerical aperture, such as microscopy, resulting in images with in- and out-of-focus regions. Therefore, methods to extend depth of field are of particular interest. Researchers have previously shown the advantages of using freeform components to extend depth of field, with each optical system requiring a specially designed phase plate. In this paper we present a method to enable extended depth-of-field imaging for a range of numerical apertures using freeform phase plates to create variable cubic wavefronts. The concept is similar to an Alvarez lens which creates variable spherical wavefronts through the relative translation of two transmissive elements with XY polynomial surfaces. We discuss design and optimization methods to enable extended depth of field for lenses with different numerical aperture values by considering through-focus variation of the point spread function and compare on- and off-axis performance through multiple metrics.

Revision of Ischnopelta Stål, 1868 with the description of twenty new species (Hemiptera: Pentatomidae: Discocephalinae)

Ischnopelta Stål, 1868 is a Discocephalini genus with three known species, I. scutellata (Signoret, 1851), I. oblonga (Fieber, 1851), and I. luteicornis (Walker, 1867), and distribution restricted to South America. The examination of 284 specimens from several localities in Venezuela, Brazil, Bolivia, Argentina, and Paraguay, revealed the existence of new species. Measurements of 24 morphometric parameters were taken using stereomicroscope and tpsDig2 version 2.16 from images captured with an MShot MD50 camera coupled to a Techno RZ stereomicroscope and edited in MShot DIS version 1.1. The genitalia of both sexes was dissected upon specimen availability, digested in KOH 10%, dehydrated in ethanol 70%, stained in Congo red (when needed), and preserved in liquid glycerin. Photographs were made in a Nikon AZ100M stereomicroscope, and a focus stacking procedure was done with Nikon NIS-Elements Ar Microscope Imaging Software. Drawings were produced over the images with a vectorial image processor. In this work Ischnopelta is revised, I. scutellata and I. luteicornis are redescribed, and keys to males and females of the species are proposed. We describe 20 new species: I. alalonga sp. n., I. anangulata sp. n., I. bechyneorum sp. n., I. confusa sp. n., I. coralinae sp. n., I. cordiformis sp. n., I. crassula sp. n., I. cristulata sp. n., I. cylindrata sp. n., I. guarani sp. n., I. impunctata sp. n., I. magna sp. n., I. marginella sp. n., I. montana sp. n., I. paiagua sp. n., I. parvula sp. n., I. pellucidula sp. n., I. ruckesi sp. n., I. vellozia sp. n., and I. wigodzinskyi sp. n.. We were unable to locate the syntypes of I. oblonga (Fieber, 1851) and the species is treated here as incertae sedis.